But for jihadis, chat rooms are the font from which they can receive messages directly from al-Qaida leaders in Yemen, North Africa, Iraq and elsewhere. The administrators who run the password-protected sites “get their information directly from the media arm of al-Qaida branches in different parts of the world,” said Aaron Y. Zelin, who runs Jihadology, an aggregator website for online jihad.

“These forums are very, very important to the movement,” said William McCants, a fellow at George Washington University’s Homeland Security Policy Institute. “These forums are really the glue that holds everybody together in these organizations.”

On March 23, a few of the top jihadi chat forums went dark. Nobody has claimed responsibility for bringing the sites down, though Zelin suspects it was an international intelligence agency trying to prevent the release of some kind of information. Although the sites regularly go down and then reappear, “this is the longest they’ve gone dark since the forums started becoming popular in 2003,” Zelin said.

One of the larger forums, Shamukh, was back online Wednesday with a statement about the blackout. “The enemies of Allah who boast of their freedoms have not spared any effort to eradicate our blessed media,” read an Arabic-language statement that was partially translated by Zelin for the NewsHour. “The Shamukh forum was targeted in this failed campaign — but even if it halted the forum, it failed to achieve its aims.”

These forums are so effective because of their authenticity. McCants said that the top sites are “stingy with passwords” and hard to join.

“There aren’t many of these forums, and al-Qaida only distributes its propaganda to one or two of these forums exclusively,” McCants said. “They’re the first place you go to get guidance from their top leadership. Any statement from Ayman al-Zawahiri or one of his lieutenants, and these forums are the first place it goes.”

Although the forums are effective at spreading the gospel of global terrorism, McCants and Zelin said they’re not good for much else. In December, McCants told a House subcommittee on counterterrorism that the talk in these forums was lots of “smoke” with almost no fire to show for it.

“All of the attacks and serious plots in the last 10 years have emanated from an actual theater of war,” Zelin said. “Some plots have emanated from these forums, but they were never serious and are always stopped because intelligence agencies are also tracking these websites.”

So if these sites are all talk, why do people visit them? According to Zelin, it’s for the same reasons that teenage gamers congregate in online forums.

“Once you have a username and password, you can post to any thread or start a thread. If people find it interesting, they’ll post to your thread. If not, they won’t. It’s just like any other online forum, but these guys are into al-Qaida,” Zelin said.

The above photo shows a July 2005 computer screen grab from the home page of the ‘Saud al Jihad’ or ‘Voice of the Jihad’. Photo by AFP/Getty Images.